ePrints@IIScePrints@IISc Home | About | Browse | Latest Additions | Advanced Search | Contact | Help

Polarization-Graded AlGaN Solar-Blind p-i-n Detector With 92% Zero-Bias External Quantum Efficiency

Kalra, Anisha and Rathkanthiwar, Shashwat and Muralidharan, Rangarajan and Raghavan, Srinivasan and Nath, Digbijoy N (2019) Polarization-Graded AlGaN Solar-Blind p-i-n Detector With 92% Zero-Bias External Quantum Efficiency. In: IEEE PHOTONICS TECHNOLOGY LETTERS, 31 (15). pp. 1237-1240.

[img] PDF
iee_pho_tec_let_31-15_1237_2019.pdf - Published Version
Restricted to Registered users only

Download (1MB) | Request a copy
Official URL: http://dx.doi.org/10.1109/LPT.2019.2923147


We report on record high zero-bias external quantum efficiency (EQE) of 92% for back-illuminated Al0.40Ga0.60N p-i-n ultra-violet (UV) photodetectors on sapphire. The zero-bias responsivity measured 211 mA/W at 289 nm, which is the highest value reported for solar-blind, p-i-n detectors realized over any epitaxial wide band-gap semiconductor. This is also the first report for a p-i-n detector, where a polarization-graded Mg-doped AlGaN layer is utilized as the p-contact layer. The devices exhibited a ten-orders of magnitude rectification, a low reverse leakage current density of 1 nA/cm(2) at 10 V, a high R(0)A product of 1.3 x 1011 Omega.cm(2) and supported fields exceeding 5 MV/cm. The light-to-dark current ratio and the UV-to-visible rejection ratio for the detectors exceeded six-orders of magnitude and the thermal noise limited detectivity (D*) measured 6.1 x 1014 cmHz(1/2)W(-1). The state-of-the-art performance parameters can be attributed to a high crystalline quality absorbing AlGaN epi-layer resulting from the use of an AlN/AlGaN superlattice buffer and an improved p-contact via polarization grading.

Item Type: Journal Article
Additional Information: copyright for this article belongs to IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Keywords: Aluminium gallium nitride (AlGaN); epitaxial growth; p-i-n photodiodes; metal organic chemical vapor deposition (MOCVD); solar-blind; ultra-violet detectors
Department/Centre: Division of Interdisciplinary Sciences > Centre for Nano Science and Engineering
Date Deposited: 03 Sep 2019 10:24
Last Modified: 03 Sep 2019 10:24
URI: http://eprints.iisc.ac.in/id/eprint/63400

Actions (login required)

View Item View Item